Type 1 is shown as a diamond-shaped yellow sign with nine yellow
circles denoting yellow retroreflectors mounted symmetrically in
three diagonal rows on the marker. Type 2 is shown as a vertical
all-yellow rectangle. Type 3 is shown as a vertical rectangle with
diagonal alternating black and yellow stripes. The stripes are at
a 45-degree angle beginning at the upper right and slanting down
to the left.